Telescopic ladder assembly

Abstract

A telescopically extendable and collapsible ladder assembly includes a top ladder section, a bottom ladder section, and one or more intermediate ladder sections. The assembly may include sliding automatic release actuators, having a slanted actuating surface for interaction with actuator surfaces of spacers provided at each end of a rung of an adjacent ladder section, such that, when a rung is moved towards the rung of an adjacent lower ladder section, the activation surfaces of the spacers push the release actuators into an unlocking position and subsequently position the rung at an anti-finger pinching distance. The top rung of the bottom ladder section may be provided with a centrally arranged grip element that forms a housing for manually operable release actuators provided at the bottom side of the rung.

The invention claimed is: 
     
       1. A telescopically extendable and collapsible ladder assembly having a top ladder section, a bottom ladder section, and one or more intermediate ladder sections;
 wherein the top ladder section and each of the one or more intermediate ladder sections have two tubular stile members arranged parallel to each other and interconnected at a top end by a ladder rung to form a U-shaped ladder section, and wherein the bottom ladder section has two tubular stile members arranged parallel to each other and interconnected by a top ladder rung and a bottom ladder rung; 
 wherein the ladder rungs are made from an aluminum tubular profile, the profile including a top wall, a bottom wall, as well as a front and a back wall extending between the top wall and the bottom wall; 
 wherein each ladder section includes a connector at each end of the rung, each connector having a rung portion connected to the end of the rung and a stile member portion connected to one of the stile members of the ladder section; 
 wherein the stile members of the top ladder section and of the one or more intermediate ladder sections are telescopically inserted into the stile members of an adjacent lower ladder section of the ladder sections, so that the one or more intermediate ladder sections and the top ladder section can be collapsed in a collapsing direction towards the bottom ladder section; 
 wherein the top rung of the bottom ladder section and the rung of each of the one or more intermediate ladder sections are provided at each end with a spacer for, when the ladder assembly is in a collapsed condition, supporting an adjacent upper ladder rung of the ladder rungs at a predetermined anti-finger pinching distance from the top wall of the ladder rung on which the spacer has been provided; 
 wherein the top rung of the bottom ladder section and the rung of each of the one or more intermediate ladder sections are provided at each end with an automatic latch mechanism, the automatic latch mechanisms being adapted for automatically locking the stile members of an adjacent higher ladder section of the ladder sections in a fully extended position of said adjacent higher ladder section; 
 wherein the automatic latch mechanisms of the intermediate ladder sections each comprise a locking pin, which locking pins are each moveably supported for movement along the rung in a longitudinal direction thereof, between a locking position, in which an end of the locking pin is inserted in an opening provided in the stile member of the adjacent upper ladder section to lock the stile members relative to each other, and an unlocking position, in which said end of said locking pin is retracted from said opening, and wherein each locking pin is biased towards the stile member, i.e. towards the locking position; 
 wherein the automatic latch mechanisms of the intermediate ladder sections each comprise an automatic release actuator, which automatic release actuators are coupled with the locking pin of the automatic latch mechanisms, for unlocking the stile member of the adjacent higher ladder section by moving the automatic release actuator from its passive position into its actuated position, and thus moving the locking pin from its locking position into its unlocking position, in order to allow for collapsing of the ladder assembly; 
 wherein the automatic latch mechanisms of the bottom ladder section each comprise a manually operable release actuator, which manually operable release actuators are coupled with the locking pin of the automatic latch mechanisms, for unlocking the stile member of the adjacent higher ladder section by moving the locking pin into its unlocking position, in order to allow for collapsing of the ladder assembly; 
 wherein the spacers are each located at a top side of their ladder rung and against the stile member of the adjacent upper ladder section, and each extend along said stile member in an upward direction between a base, which base is located at the top side of the rung, and a top end, which top end is provided with a slanted actuating surface, which actuating surface is at its top end located adjacent the stile member and veers away from the stile member in the downward direction; 
 wherein the ladder rung of the intermediate ladder section is at its bottom side at both ends provided with a slanted support surface, extending parallel to and vertically above the actuating surface of the spacer of the adjacent lower ladder section, such that when the ladder assembly is in its collapsed positon, the support surfaces rest against the actuating surfaces of the spacers of the adjacent lower ladder section, to keep the ladder rungs at the predetermined anti-finger pinching distance; 
 wherein the automatic release actuators are sliding actuators moveably supported for movement along the rung in a longitudinal direction thereof, and wherein the automatic release actuators are each provided with a slanted actuating surface extending parallel to the actuating surface of the spacer of the adjacent lower ladder section, and wherein said actuating surface of the release actuator, when the release actuator is in its rest position, is located vertically above the actuating surface of the spacer of the adjacent lower ladder section; and 
 wherein, when the ladder rung is moved towards the ladder rung of the adjacent lower ladder section, the activation surfaces of the spacers of the ladder rung of the adjacent lower ladder section first contacts the actuating surfaces of the sliding automatic release actuators, pushing the sliding automatic release actuators into their unlocking position, and subsequently contact the support surfaces of the ladder rung, positioning the ladder rung at the predetermined anti-finger pinching distance from the ladder rung of the adjacent lower ladder section. 
 
     
     
       2. The ladder assembly according to  claim 1 , wherein the ladder stile members each have a circular cross section comprising a flat section facing the rung which flat section extends perpendicular to a longitudinal axis of the rung, and wherein the spacers are each positioned against this flat section of the adjacent upper ladder stile members. 
     
     
       3. The ladder assembly according to  claim 1 , wherein the support surfaces of ladder rung are located below the locking pins of the latch mechanisms of said ladder rung. 
     
     
       4. The ladder assembly according to  claim 1 , wherein the support surfaces of the ladder rung are located level with or even above the locking pins of the latch mechanisms of said ladder rung. 
     
     
       5. The ladder assembly according to  claim 1 , wherein the connector is made out of plastic using an injection moulding technique, and wherein the connector is at its top provided with the spacer, and at its bottom side provided with the support surface, which spacer and support surface form an integral part with the connector. 
     
     
       6. The ladder assembly according to  claim 1 , wherein each rung is provided with a recess comprising the support surface. 
     
     
       7. The ladder assembly according to  claim 1 , wherein the sliding automatic release actuators are provided below the rung, on the outside thereof, and extend through a slot in the bottom wall of the rung and/or connector into the interior of the rung and/or connector. 
     
     
       8. The ladder assembly according to  claim 1 , wherein the ladder rungs are at their bottom side provided with an elongated recessed portion extending over the length thereof, and the automatic release actuators are arranged in said recessed portion. 
     
     
       9. The ladder assembly according to  claim 1 , wherein each connector is at it's stile member portion provided with a ring shaped section for receiving the stile member of the ladder section, which is to be inserted into the ladder rung. 
     
     
       10. The ladder assembly according to  claim 1 , wherein the rung of each intermediate ladder section is, in addition to the automatic release actuators, provided with one or more manually operable release actuators connected to the latch mechanisms of the rung to allow for manual unlocking of the stile members of said adjacent higher ladder section by a user in order to allow for a section-by-section manually release and collapsing of the ladder assembly. 
     
     
       11. A loft ladder including a ladder assembly according  claim 1 . 
     
     
       12. A stepladder having a first stepladder assembly and a second stepladders assembly hinged to one another so as to be in a storage position folded against one another and an operative position similar to an inverted V at least one of the stepladder assemblies being a ladder assembly according to  claim 1 . 
     
     
       13. A work platform including a ladder assembly according to  claim 1 . 
     
     
       14. The ladder assembly according to  claim 1 , wherein the support surfaces of the ladder rung are located centrally below the locking pins of the latch mechanisms of said ladder rung. 
     
     
       15. The ladder assembly according to  claim 1 , wherein each rung is provided with a recess comprising the support surface, which recess is a one side open chamber in a bottom of the connector, wherein the support surface forms a top wall of said chamber, and wherein one sidewall of the chamber is formed by the stile member.